WooCommerce - Show stock level in catalogue

<?php
  // WooCommerce hook to show stock level in the catalogue
  add_action('woocommerce_after_shop_loop_item_title', 'show_stock', 15);
  function show_stock() {
    global $product;
    $stock = intval($product->stock);
    switch ($stock) {
      case 0:
        $text = 'Sold';
        break;
      case 1:
        $text = 'Last one!';
        break;
      default:
        $text = "Stock: ".$stock;
    }
    echo '<span class="show_stock">'.$text.'</span>'.PHP_EOL;
  }